1. Field of the Invention
The present invention relates to the field recycling and refurbishing of plastic containers and more particularly relates to a method and apparatus for removing blemishes from polycarbonate water bottles.
2. Description of the Prior Art
Bottled water, which is widely used thoughout many parts of the country and world where tap water is either unpalatable or not reliably potable, has traditionally been delivered and stored for consumer use in large five gallon glass bottles. Although durable, such glass bottles are very expensive to manufacture, heavy to handle, and susceptible to breakage. More recently, glass water bottles have been increasingly replaced by five gallon plastic water bottles, and in particular, polycarbonate water bottles. The polycarbonate water bottles have the advantage of not only being more inexpensively produced, but of being substantially lighter and virtually unbreakable.
However, despite the extreme ruggedness of such plastic bottles, the material of such bottles is particularly susceptible to scuffing, abrasion, and scratching. Even though the plastic bottles are less expensive than the glass bottles that preceded them, their cost is not so trivial that they are disposable. Consequently, as with glass bottles, plastic water bottles are returned, sanitized and recycled a number of times.
During filling, washing, transporting and other normal handling operations, the exterior of the plastic bottles becomes scuffed and scratched. These surface blemishes are accumlated during repeated handling to the point that the plastic bottle acquires a scratched or cloudy appearance, thereby tending to give the illusion that the water contained within the bottle is similarly clouded by contaminants. At this point, continued used of the bottle becomes commercially unacceptable, and it must be discarded, despite the fact that the bottle actually has a substantial usable lifetime remaining.
What is need, then, is a method and apparatus to remove scuff marks and other scratches from the exterior of plastic containers without affecting the strength, surface hardness, or inert properties of the interior of the container which is in intimate contact with a consumable substance or liquid.